M.C. v. T.K., 463 Mass. 226

Parties never married and share joint legal custody and substantially equal physical custody of their three-year-old daughter.
Probate and Family Court ordered the father to pay $454 weekly child support, which effectively equalized the parties’ net incomes.
Father’s assets and income were substantial; he testified to $147,000+ net income (per year) based on spending, while mother’s net income was about $99,744 per year.
2006 Massachusetts child support guidelines did not apply to shared custody or combined income exceeding $135,000; principles nonetheless guided discretion.
Court vacates the judgment to the extent it orders child support and related costs, remanding for determination under applicable guidelines and current income, if any.

Issue	Plaintiff's Argument	Defendant's Argument	Held
May child support be awarded in shared custody, and is income equalization permissible?	Father: shared custody precludes support and income equalization; argues against support and for no equalization.	Mother: support may be appropriate but should reflect guidelines and avoid pure income equalization.	Income equalization is inappropriate; support may be considered under guidelines principles with remand for proper determination.
Was imputing income to the father appropriate?	Father contends retirement and assets should not drive imputations; claims insufficient findings.	Mother contends the judge properly imputed income based on spending and asset use, with credible record.	Imputation to father was supported by the record; findings deemed credible and appropriate.
Should the mother bear child-care and private school/extracurricular costs under the judgment?	Father argues such allocations are inconsistent with shared custody rationale and current incomes.	Mother argued for allocation of certain child-related expenses to the other party as appropriate under guidelines.	Allocation of child-care and private school/extracurricular costs must be reconsidered on remand under applicable guidelines.

Department of Revenue v. Mason M., 439 Mass. 665 (2003) (guidelines emphasize proportionality and living standards; not to fully equalize)
J.S. v. C.C., 454 Mass. 652 (2009) (shared custody scenarios may be guided by guidelines principles)
Smith v. Edelman, 68 Mass. App. Ct. 549 (2007) (maintaining family standard of living has limits; avoid pure equalization)
Crowe v. Fong, 45 Mass. App. Ct. 673 (1998) (credit considerations and evidence-based income determinations in support awards)
Brooks v. Piela, 61 Mass. App. Ct. 731 (2004) (custodial parents' costs and standard of living considerations in awards)
Pearson v. Pearson, 52 Mass. App. Ct. 156 (2001) (rejects pure income-sharing approaches in child support)
Kane v. Kane, 13 Mass. App. Ct. 557 (1982) (imputation of income based on available records and expenditures)